package com.demo.utils;

import com.demo.common.IMessageConstants;
import lombok.extern.log4j.Log4j2;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Objects;

/**
 * http相关工具类
 * @Author liuyj
 * @Date 2019-11-18 19:26:20
 */
@Log4j2
public class HttpUtil {

    private static String UNKNOWN = "unknown";

    /**
     * 获取request
     * @return
     */
    public static HttpServletRequest getRequest(){
        HttpServletRequest request= null;
        try {
            ServletRequestAttributes servletRequestAttributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
            if(null != servletRequestAttributes){
                request = servletRequestAttributes.getRequest();
            }
        } catch (Exception e) {
            log.error(IMessageConstants.EXCEPTION_LOG, e);
        }
        return request;
    }
    /**
     * 获取用户真实IP地址，不使用request.getRemoteAddr();的原因是有可能用户使用了代理软件方式避免真实IP地址,
     *
     * 可是，如果通过了多级反向代理的话，X-Forwarded-For的值并不止一个，而是一串IP值，究竟哪个才是真正的用户端的真实IP呢？
     * 答案是取X-Forwarded-For中第一个非unknown的有效IP字符串。
     *
     * 如：X-Forwarded-For：192.168.1.110, 192.168.1.120, 192.168.1.130,
     * 192.168.1.100
     *
     * 用户真实IP为： 192.168.1.110
     *
     * @param request
     * @return
     */
    public static String getIpAddress(HttpServletRequest request) {
        String ip = request.getHeader("x-forwarded-for");
        if (ip == null || ip.length() == 0 || UNKNOWN.equalsIgnoreCase(ip)) {
            ip = request.getHeader("Proxy-Client-IP");
        }
        if (ip == null || ip.length() == 0 || UNKNOWN.equalsIgnoreCase(ip)) {
            ip = request.getHeader("WL-Proxy-Client-IP");
        }
        if (ip == null || ip.length() == 0 || UNKNOWN.equalsIgnoreCase(ip)) {
            ip = request.getHeader("HTTP_CLIENT_IP");
        }
        if (ip == null || ip.length() == 0 || UNKNOWN.equalsIgnoreCase(ip)) {
            ip = request.getHeader("HTTP_X_FORWARDED_FOR");
        }
        if (ip == null || ip.length() == 0 || UNKNOWN.equalsIgnoreCase(ip)) {
            ip = request.getRemoteAddr();
            if ("127.0.0.1".equals(ip) || "0:0:0:0:0:0:0:1".equals(ip)) {
                //根据网卡取本机配置的IP
                InetAddress inet = null;
                try {
                    inet = InetAddress.getLocalHost();
                } catch (UnknownHostException e) {
                    e.printStackTrace();
                }
                if (Objects.nonNull(inet)) {
                    ip = inet.getHostAddress();
                }
            }
        }
        //对于通过多个代理的情况，第一个IP为客户端真实IP,多个IP按照','分割  "***.***.***.***".length() = 15
        if (ip != null && ip.length() > 15) {
            if (ip.indexOf(",") > 0) {
                ip = ip.substring(0, ip.indexOf(","));
            }
        }
        return ip;
    }

    /**
     * @Title: getProxy
     * @Description: 因为接口提供方只允许白名单固定IP服务器访问，故本地调试发送请求时需要用到代理。<br>
     *               114.115.128.140 SOCKS5 端口:3232 用户名:arpa密码:admin<br>
     *               114.115.128.140 HTTP 端口:3231 无用户名密码<br>
     *               <a href='https://www.cnblogs.com/binyue/p/4103646.html'>相关文档</a>
     * @return
     */
    /*public static Proxy getProxy() {
        Authenticator.setDefault(new Authenticator() {
            @Override
            protected PasswordAuthentication getPasswordAuthentication() {
                String pswd = "admin";
                return new PasswordAuthentication("arpa", pswd.toCharArray());
            }
        });
        InetSocketAddress address = new InetSocketAddress("114.115.128.140", 3232);
        return new Proxy(Proxy.Type.SOCKS, address);
    }*/
}
